<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>小黑猫</title>

  <script type='text/javascript' src='https://cdn.bootcss.com/three.js/r75/three.min.js'></script>
  <script type='text/javascript' src='./js/TweenMax.min.js'></script>
  <script type='text/javascript' src='./js/OrbitControls.js'></script>
  <script type='text/javascript' src='./js/Cat.js'></script>

  <style type="text/css">
    * {
      margin: 0px;
      padding: 0px;
    }

    #world {
      position: absolute;
      width: 100%;
      height: 100%;
      background-color: #6ecccc;
      overflow: hidden;
    }

    #credits {
      position: absolute;
      width: 100%;
      margin: auto;
      bottom: 0;
      margin-bottom: 20px;
      font-family: 'Open Sans', sans-serif;
      color: #328685;
      font-size: 0.7em;
      text-transform: uppercase;
      text-align: center;
    }

    #credits a {
      color: #328685;
    }

    #credits a:hover {
      color: #630d15;
    }

    h1 {
      text-align: center;
      background-color: rgb(110, 204, 204);
    }
  </style>
</head>

<body>
  <h1>为了怕您在系统中无聊,特意为您准备了招待的小黑猫</h1>
  <div id="world"></div>
</body>
<script>
  //THREEJS RELATED VARIABLES 

  var scene,
    camera, fieldOfView, aspectRatio, nearPlane, farPlane,
    gobalLight, shadowLight, backLight,
    renderer,
    container,
    controls;

  //SCREEN & MOUSE VARIABLES

  var HEIGHT, WIDTH, windowHalfX, windowHalfY,
    mousePos = { x: 0, y: 0 },
    oldMousePos = { x: 0, y: 0 },
    ballWallDepth = 28;


  //3D OBJECTS VARIABLES

  var hero;

  //INIT THREE JS, SCREEN AND MOUSE EVENTS

  function initScreenAnd3D() {

    HEIGHT = window.innerHeight;
    WIDTH = window.innerWidth;
    windowHalfX = WIDTH / 2;
    windowHalfY = HEIGHT / 2;

    scene = new THREE.Scene();
    aspectRatio = WIDTH / HEIGHT;
    fieldOfView = 50;
    nearPlane = 1;
    farPlane = 2000;
    camera = new THREE.PerspectiveCamera(
      fieldOfView,
      aspectRatio,
      nearPlane,
      farPlane
    );
    camera.position.x = 0;
    camera.position.z = 300;
    camera.position.y = 250;
    camera.lookAt(new THREE.Vector3(0, 60, 0));

    renderer = new THREE.WebGLRenderer({ alpha: true, antialias: true });
    renderer.setPixelRatio(window.devicePixelRatio);
    renderer.setSize(WIDTH, HEIGHT);
    renderer.shadowMapEnabled = true;

    container = document.getElementById('world');
    container.appendChild(renderer.domElement);

    window.addEventListener('resize', handleWindowResize, false);
    document.addEventListener('mousemove', handleMouseMove, false);
    document.addEventListener('touchmove', handleTouchMove, false);

    /*
    controls = new THREE.OrbitControls(camera, renderer.domElement);
    controls.minPolarAngle = -Math.PI / 2; 
    controls.maxPolarAngle = Math.PI / 2;
    controls.noZoom = true;
    controls.noPan = true;
    //*/


  }

  function handleWindowResize() {
    HEIGHT = window.innerHeight;
    WIDTH = window.innerWidth;
    windowHalfX = WIDTH / 2;
    windowHalfY = HEIGHT / 2;
    renderer.setSize(WIDTH, HEIGHT);
    camera.aspect = WIDTH / HEIGHT;
    camera.updateProjectionMatrix();
  }

  function handleMouseMove(event) {
    mousePos = { x: event.clientX, y: event.clientY };
  }

  function handleTouchMove(event) {
    if (event.touches.length == 1) {
      event.preventDefault();
      mousePos = { x: event.touches[0].pageX, y: event.touches[0].pageY };
    }
  }

  function createLights() {
    globalLight = new THREE.HemisphereLight(0xffffff, 0xffffff, .5)

    shadowLight = new THREE.DirectionalLight(0xffffff, .9);
    shadowLight.position.set(200, 200, 200);
    shadowLight.castShadow = true;
    shadowLight.shadowDarkness = .2;
    shadowLight.shadowMapWidth = shadowLight.shadowMapHeight = 2048;

    backLight = new THREE.DirectionalLight(0xffffff, .4);
    backLight.position.set(-100, 100, 100);
    backLight.castShadow = true;
    backLight.shadowDarkness = .1;
    backLight.shadowMapWidth = shadowLight.shadowMapHeight = 2048;

    scene.add(globalLight);
    scene.add(shadowLight);
    scene.add(backLight);
  }

  function createFloor() {
    floor = new THREE.Mesh(new THREE.PlaneBufferGeometry(1000, 1000), new THREE.MeshBasicMaterial({ color: 0x6ecccc }));
    floor.rotation.x = -Math.PI / 2;
    floor.position.y = 0;
    floor.receiveShadow = true;
    scene.add(floor);
  }

  function createHero() {
    hero = new Cat();
    scene.add(hero.threeGroup);
  }

  function createBall() {
    ball = new Ball();
    scene.add(ball.threeGroup);
  }

  // BALL RELATED CODE


  var woolNodes = 10,
    woolSegLength = 2,
    gravity = -.8,
    accuracy = 1;


  Ball = function () {

    var redMat = new THREE.MeshLambertMaterial({
      color: 0x630d15,
      shading: THREE.FlatShading
    });

    var stringMat = new THREE.LineBasicMaterial({
      color: 0x630d15,
      linewidth: 3
    });

    this.threeGroup = new THREE.Group();
    this.ballRay = 8;

    this.verts = [];

    // string
    var stringGeom = new THREE.Geometry();

    for (var i = 0; i < woolNodes; i++) {
      var v = new THREE.Vector3(0, -i * woolSegLength, 0);
      stringGeom.vertices.push(v);

      var woolV = new WoolVert();
      woolV.x = woolV.oldx = v.x;
      woolV.y = woolV.oldy = v.y;
      woolV.z = 0;
      woolV.fx = woolV.fy = 0;
      woolV.isRootNode = (i == 0);
      woolV.vertex = v;
      if (i > 0) woolV.attach(this.verts[(i - 1)]);
      this.verts.push(woolV);

    }
    this.string = new THREE.Line(stringGeom, stringMat);

    // body
    var bodyGeom = new THREE.SphereGeometry(this.ballRay, 5, 4);
    this.body = new THREE.Mesh(bodyGeom, redMat);
    this.body.position.y = -woolSegLength * woolNodes;

    var wireGeom = new THREE.TorusGeometry(this.ballRay, .5, 3, 10, Math.PI * 2);
    this.wire1 = new THREE.Mesh(wireGeom, redMat);
    this.wire1.position.x = 1;
    this.wire1.rotation.x = -Math.PI / 4;

    this.wire2 = this.wire1.clone();
    this.wire2.position.y = 1;
    this.wire2.position.x = -1;
    this.wire1.rotation.x = -Math.PI / 4 + .5;
    this.wire1.rotation.y = -Math.PI / 6;

    this.wire3 = this.wire1.clone();
    this.wire3.rotation.x = -Math.PI / 2 + .3;

    this.wire4 = this.wire1.clone();
    this.wire4.position.x = -1;
    this.wire4.rotation.x = -Math.PI / 2 + .7;

    this.wire5 = this.wire1.clone();
    this.wire5.position.x = 2;
    this.wire5.rotation.x = -Math.PI / 2 + 1;

    this.wire6 = this.wire1.clone();
    this.wire6.position.x = 2;
    this.wire6.position.z = 1;
    this.wire6.rotation.x = 1;

    this.wire7 = this.wire1.clone();
    this.wire7.position.x = 1.5;
    this.wire7.rotation.x = 1.1;

    this.wire8 = this.wire1.clone();
    this.wire8.position.x = 1;
    this.wire8.rotation.x = 1.3;

    this.wire9 = this.wire1.clone();
    this.wire9.scale.set(1.2, 1.1, 1.1);
    this.wire9.rotation.z = Math.PI / 2;
    this.wire9.rotation.y = Math.PI / 2;
    this.wire9.position.y = 1;

    this.body.add(this.wire1);
    this.body.add(this.wire2);
    this.body.add(this.wire3);
    this.body.add(this.wire4);
    this.body.add(this.wire5);
    this.body.add(this.wire6);
    this.body.add(this.wire7);
    this.body.add(this.wire8);
    this.body.add(this.wire9);

    this.threeGroup.add(this.string);
    this.threeGroup.add(this.body);

    this.threeGroup.traverse(function (object) {
      if (object instanceof THREE.Mesh) {
        object.castShadow = true;
        object.receiveShadow = true;
      }
    });

  }

  /* 
  The next part of the code is largely inspired by this codepen :
  https://codepen.io/dissimulate/pen/KrAwx?editors=001
  thanks to dissimulate for his great work
  */

  /*
  Copyright (c) 2013 dissimulate at Codepen
  
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
  
  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.
  
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  THE SOFTWARE.
  */



  WoolVert = function () {
    this.x = 0;
    this.y = 0;
    this.z = 0;
    this.oldx = 0;
    this.oldy = 0;
    this.fx = 0;
    this.fy = 0;
    this.isRootNode = false;
    this.constraints = [];
    this.vertex = null;
  }


  WoolVert.prototype.update = function () {
    var wind = 0;//.1+Math.random()*.5;
    this.add_force(wind, gravity);

    nx = this.x + ((this.x - this.oldx) * .9) + this.fx;
    ny = this.y + ((this.y - this.oldy) * .9) + this.fy;
    this.oldx = this.x;
    this.oldy = this.y;
    this.x = nx;
    this.y = ny;

    this.vertex.x = this.x;
    this.vertex.y = this.y;
    this.vertex.z = this.z;

    this.fy = this.fx = 0
  }

  WoolVert.prototype.attach = function (point) {
    this.constraints.push(new Constraint(this, point));
  };

  WoolVert.prototype.add_force = function (x, y) {
    this.fx += x;
    this.fy += y;
  };

  Constraint = function (p1, p2) {
    this.p1 = p1;
    this.p2 = p2;
    this.length = woolSegLength;
  };

  Ball.prototype.update = function (posX, posY, posZ) {

    var i = accuracy;

    while (i--) {

      var nodesCount = woolNodes;

      while (nodesCount--) {

        var v = this.verts[nodesCount];

        if (v.isRootNode) {
          v.x = posX;
          v.y = posY;
          v.z = posZ;
        }

        else {

          var constraintsCount = v.constraints.length;

          while (constraintsCount--) {

            var c = v.constraints[constraintsCount];

            var diff_x = c.p1.x - c.p2.x,
              diff_y = c.p1.y - c.p2.y,
              dist = Math.sqrt(diff_x * diff_x + diff_y * diff_y),
              diff = (c.length - dist) / dist;

            var px = diff_x * diff * .5;
            var py = diff_y * diff * .5;

            c.p1.x += px;
            c.p1.y += py;
            c.p2.x -= px;
            c.p2.y -= py;
            c.p1.z = c.p2.z = posZ;
          }

          if (nodesCount == woolNodes - 1) {
            this.body.position.x = this.verts[nodesCount].x;
            this.body.position.y = this.verts[nodesCount].y;
            this.body.position.z = this.verts[nodesCount].z;

            this.body.rotation.z += (v.y <= this.ballRay) ? (v.oldx - v.x) / 10 : Math.min(Math.max(diff_x / 2, -.1), .1);
          }
        }

        if (v.y < this.ballRay) {
          v.y = this.ballRay;
        }
      }
    }

    nodesCount = woolNodes;
    while (nodesCount--) this.verts[nodesCount].update();

    this.string.geometry.verticesNeedUpdate = true;


  }

  Ball.prototype.receivePower = function (tp) {
    this.verts[woolNodes - 1].add_force(tp.x, tp.y);
  }

  // Enf of the code inspired by dissmulate


  // Make everything work together :

  var t = 0;

  function loop() {
    render();

    t += .05;
    hero.updateTail(t);

    var ballPos = getBallPos();
    ball.update(ballPos.x, ballPos.y, ballPos.z);
    ball.receivePower(hero.transferPower);
    hero.interactWithBall(ball.body.position);

    requestAnimationFrame(loop);
  }


  function getBallPos() {
    var vector = new THREE.Vector3();

    vector.set(
      (mousePos.x / window.innerWidth) * 2 - 1,
      - (mousePos.y / window.innerHeight) * 2 + 1,
      0.1);

    vector.unproject(camera);
    var dir = vector.sub(camera.position).normalize();
    var distance = (ballWallDepth - camera.position.z) / dir.z;
    var pos = camera.position.clone().add(dir.multiplyScalar(distance));
    return pos;
  }

  function render() {
    if (controls) controls.update();
    renderer.render(scene, camera);
  }

  window.addEventListener('load', init, false);

  function init(event) {
    initScreenAnd3D();
    createLights();
    createFloor()
    createHero();
    createBall();
    loop();
  }

</script>

</html>